Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
“LILIES” AGAINST “THE LION”
From the point of view of war at sea the eighteenth century has largely been a century frigates. For over a hundred years three major powers of Europe were engaged in a military...
“PANTHER HUNTER”
Shortly after the outbreak of the Second world war, the Germans faced a serious crisis in the anti-tank artillery. Their primary 37-mm gun Cancer 35/36 was completely powerless against...
